The present invention relates to vehicle-mounted electronic equipment with an operating unit attached removably to an equipment body thereof, and more particularly to an apparatus for locking the operating unit to an equipment body.
Generally, a system is known which removes vehicle-mounted electronic equipment and especially an acoustic device body from a vehicle among various vehicle-mounted electronic equipment; a so-called take-away system, in order to prevent a theft of the vehicle-mounted acoustic device. However, when this system is employed, the vehicle-mounted acoustic device is large-sized and heavy, so that it is inconvenient for the user to remove the acoustic device and carry it. Thus, in actual use, when the user leaves his vehicle for only a short time period, the user does not carry the acoustic device in many cases, so that the function of preventing a theft of the take-away system is not sufficiently utilized.
Recently, acoustic devices have been multiplied in function, so that the weight of the acoustic devices has increased. Therefore, carrying the acoustic device is more troublesome and the rate of use of the theft preventing function has been further reduced and hence the effect of the theft prevention has further been reduced as well. In addition, the recent acoustic devices have a built-in high output amplifier so that directly after the use of the acoustic device, the device body has been raised to a considerably high temperature due to generation of heat in the amplifier. When such high-temperature device is to be carried, there is a danger of the user being burnt.
In order to avoid such danger, a removable operating unit attaching system in which only an operating unit with buttons for operating the device is removed from the device body has been proposed. In this system, when the user leaves his vehicle, he removes only the operating unit from the device body so as to disable the operation of the device body.
In such removable operation unit attaching system, only the operating unit which is very light, compact and convenient to carry compared to the device body is required to be carried , so that the rate of use of the theft preventing function is greatly increased to thereby ensure a high theft preventing effect. Since the operating unit is provided with no elements which would be heated by heat produced by the amplifier, there is no danger of the user being burnt in portage and hence the operating unit is excellent from a standpoint of safety. The removable operating unit attaching system has such advantages, so that the demand therefor tends to increase, and various operating units having various sizes and shapes have been developed at present.
For example, a large operating unit having the same size as the front panel of an acoustic device has been proposed. Such an operating unit is constructed such that when it is removed by the user from the device body, the device body is completely disabled. After such operating unit is removed, no operating buttons, which would cause one to recognize the acoustic device, are disposed on the front panel of the device body left on the vehicle. Such structure greatly reduces a probability of theft of the device body left on the vehicle or produces an excellent theft preventing effect advantageously.
In the vehicle-mounted acoustic device with such operating unit, an operating unit locking apparatus which locks the operating unit to the device body is required to prevent slippage of the operating unit from the vehicle due to vibrations of the vehicle. Especially, when the operating unit is large-sized, a locking device which provides a large locking force is required. Therefore, an operating unit locking apparatus is required to be realized which provides a large locking force, is capable of locking the operating unit securely and easily to the vehicle, and removing the operating unit easily.